PMA,
TL071 usually HAS stability issues, especially in a more complex circuit!
Thanks PMA for information this is confirm what I juat try a few minutes ago when I changed the TL071 with another one with different date code and the problem are gone.
I just do not feel comfort maybe its just luck or what ever the basic problem with TL071 still exist. So may I ask what any one else will do if you only has two more choices for op amp LM318 or NE5534
Thanks.
I am hunt mostly for stability right know
TL071 usually HAS stability issues, especially in a more complex circuit!
Thanks PMA for information this is confirm what I juat try a few minutes ago when I changed the TL071 with another one with different date code and the problem are gone.
I just do not feel comfort maybe its just luck or what ever the basic problem with TL071 still exist. So may I ask what any one else will do if you only has two more choices for op amp LM318 or NE5534
Thanks.
I am hunt mostly for stability right know
The download link works fine for me, however as mentioned and discussed in another thread here, there are currently some problems with my new Joomla based website and some IExplorer versions....
Try copy and and paste this address directly into your browser;
http://www.audio-circuit.dk/lynx/LYNX-v3-0-QAG.pdf
Try copy and and paste this address directly into your browser;
http://www.audio-circuit.dk/lynx/LYNX-v3-0-QAG.pdf
Hi Jan,
I'am on searching to build a power amp for secondary sound systeme. The goal is to limit coast and do it with a maximum of parts I have on Hand. LYNX seems to be a good way. I have OPA627, MJE15030/15031, about 100 of each MJL3281A/MJL1302A, 2 toroids trafo (330VA 1x25V, 15v-0-15V/0,8A), 4x22.000µF/40V mallory, 2 heatsink (230x200x40mm). I could build a "low" LYNX power version but with High current capacity. Did this seems realistic to you. To go for, i have to redrawn the pcb as i been abble, through a good local shop, to realize double side (without metalized holes) prototype pcb, but with eagle I could'nt place parts with 45° orientation. So i need to replace all this parts, but all other will be conservated (place and rooting). For parts value adaptation I see many information in your assembling guide.
With the supply parts I could expect +/- 34VDC rail, what amount of power could I expect?
Best regards Marc
I'am on searching to build a power amp for secondary sound systeme. The goal is to limit coast and do it with a maximum of parts I have on Hand. LYNX seems to be a good way. I have OPA627, MJE15030/15031, about 100 of each MJL3281A/MJL1302A, 2 toroids trafo (330VA 1x25V, 15v-0-15V/0,8A), 4x22.000µF/40V mallory, 2 heatsink (230x200x40mm). I could build a "low" LYNX power version but with High current capacity. Did this seems realistic to you. To go for, i have to redrawn the pcb as i been abble, through a good local shop, to realize double side (without metalized holes) prototype pcb, but with eagle I could'nt place parts with 45° orientation. So i need to replace all this parts, but all other will be conservated (place and rooting). For parts value adaptation I see many information in your assembling guide.
With the supply parts I could expect +/- 34VDC rail, what amount of power could I expect?
Best regards Marc
ACD said:
Thanks ACD, this "low power" version wil be more than enough for my needs. I have the zener resistor calaculation in mind no soucy. If i take the value from 55vdc version, in my case I will not have enough voltage for OPA627 supply. I must study the output protection calculation to match it for my rails voltage.
You are saying that you didn't match small bipolar, what about output ones? Since they are in parallel they should be?
best regards Marc
I do some rapid calculations :
- For zener resistor : for 30Vdc rail => (30-15)/0.02=750R
for 35Vdc rail => (35-15)/0.02=1K
- For output protection :
The soa MJL3281A SOA curve gives me 5.5A at 35V for 1s
So 5.5x0.33=1.8v across R128 to R136
V across R124 : 1.8-0.6=1.2V => 1.2/0.006=200R=>180R 2W resistor.
Seems that good to you? Since I don't know what DC rail i will have after filtering (may between 30 and 35V) in what range can play with the zener resistor? If i take the 35V case (1K zener resistor), i will not have enough rail voltage when this is lower than predicted. With amount of VA the trafo I have (2x336VA) i assume to have enough current capacity for my project.
Marc
- For zener resistor : for 30Vdc rail => (30-15)/0.02=750R
for 35Vdc rail => (35-15)/0.02=1K
- For output protection :
The soa MJL3281A SOA curve gives me 5.5A at 35V for 1s
So 5.5x0.33=1.8v across R128 to R136
V across R124 : 1.8-0.6=1.2V => 1.2/0.006=200R=>180R 2W resistor.
Seems that good to you? Since I don't know what DC rail i will have after filtering (may between 30 and 35V) in what range can play with the zener resistor? If i take the 35V case (1K zener resistor), i will not have enough rail voltage when this is lower than predicted. With amount of VA the trafo I have (2x336VA) i assume to have enough current capacity for my project.
Marc
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